Plug-in pitot-static tube



May 25,'1954 J. A. MORRIS ETAL 2,679,163

PLUGJN PIToT-sTATIc TUBE Filed March 3, 1953 ATTORNEYS INVENTORS JOHN ARTH MO S HARRY E. LER N, JR.

Patented May 25, 1954 PLUG-IN PITOT-STATIC TUBE John A. Morris, Farrell, and Harry E. Ellerman,

Jr., Sharon, Pa., assignors, by mesne assignments, to the United States of America as represented by the Secretary of the Navy Application March 3, 1953, Serial No. 340,034

This invention relates to improvements in Pitot tubes. l

When a water test run of a torpedo is to be made it is common practice to provide it with a Pitot tube for obtaining the static and dynamic Water pressures along its run, these pressures being communicated to suitable instruments which record data from which velocity and/or depth of submergence of the torpedo may be determined. When the torpedo is retrieved, consid erable care must be exercised in handling the torpedo to prevent breakage of the Pitot tube, which is quite fragile. This careful handling and possible breakage of the Pitot tube could be obviated if the Pitot tube could be readily removed from the torpedo prior to retrieving. This has not been practical, however, since the Pitot tubes formerly employed required opening of the torpedo to disconnect them or otherwise required the disconnection of cumbersome pipe fittings. It will now become apparent that the provision of a Pitot tube which could be readily attached to a torpedo prior to a test run, and readily detached from the torpedo at the end of its run and prior to retrieving it, would advantageously facilitate the retrieving operation.

One of the objects of the invention is to provide a Pitot tube assembly which may be readily attached and detached from its carrying support.

Another object is to provide a novel carrying support for the Pitot tube assembly.

Another object is to provide a novel Pitot tube and carrying support for use on torpedoes.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

Fig. 1 is a side elevation of the subject of the invention, a portion being broken away, the forward end of a torpedo being shown by dotted lines;

Fig. 2 is an enlarged section taken on line 2 2, Fig. 1;

Fig. 3 is an enlarged fragmentary section taken on line 3 3, Fig. 1; and

Fig. 4 is a rear elevation of Fig. 3 as viewed in the direction of arrow ll.

Referring in detail to the drawing, the invention comprises, in general, a support member l and a Pitot tube assembly Il. The Pitot tube assembly comprises a pair of circular tubes I2, I3 which are securedin concentric relationship by a head member I4, the latter having a bore l5 1 Claim. (Cl. 'i3-212) for receiving the forward endof tube I3, a velocity pressure communicating bore I5a communicating with the bore of tube I 3, and a concentric surface I6 thereon over which the forward end of tube I2 telescopes. Braze or solder joints I1, I'Iapermanently retain this assembly together. Tube I2 is provided with external threads I9 near its rear end, the tube also being machined circular to the root diameter of the threads to provide a tubular unthreaded portion 20 between the threaded portion and the rearmost end of the tube. A plurality of angularly spaced apertures I8 are provided in tube I2 intermediate its ends which communicate ambient static pressure to the space between tubes I2, I3.

Pitot tube support member I0, which also forms a closure for the forward end of torpedo T, is secured to the latter by a plurality of angularly spaced cap screws (not shown) which extend through angularly spaced apertures 2I and threadedly engage the torpedo. A central portion of this member is provided with concentric bores 22, 23, the former telescopically receiving unthreaded portion 20 of the tube I2 and the latter similarly receiving a portion of tube I3. Bore 22 is also provided with a threaded portion 24 which threadedly receives threads I3 on tube I2. An O seal ring 25, disposed in a suitable annular channel in member I0 surrounds unthreaded portion 20 and a similar seal ring 26 surrounds tube I3 near its rear end.

A plate 21 is secured to the rear face of member I 0 by a plurality of cap screws 28, this plate being provided with a threaded opening 23 which communicates with tube I3, and another threaded opening 30 which communicates with the annular space between the tubes through a drilled port 3| and annular space 32. The threaded openings just referred to are provided with suitable pipe couplings (not shown) to communicate the tubes with conduits extending to the recording instrumentation.

In the use of the device, the rear end of the Pitot tube assembly is applied to the concentric bores in the Pitot tube support member and rotated until disposed in the position shown. At the end of the run, and prior to retrieving the torpedo, the Pitot tube assembly is rotated in the opposite direction and removed from the support member. As will be apparent, both of the procedures may be quickly performed without disturbing any of the more permanent connections between the Pitot tube assembly and the instrumentation.

Obviously many modifications and variations of the present invention are possible in the light static pressure tube, a third bore in said member of the above teachings. It is therefore to be disposed axially of the rst and second named understood that within the scope of the appended bores adapted to telescopically receive a portion claim the invention may be practiced otherwise 0f the velocity pressure tube extending beyond than as specically described. 5 the rear end of the static pressure tube, a pipe What I claim is: connection disposed at a rear face of said member In torpedoeapparatns fer measuringfuid presvX,.in,-axia1.alignirient With-ssad vvelocity pressure sures,ecompizising;.fassupportsmember forming a '.tubaza ,pipejzconnectioirldisposed at :aiirear face of closure for the front end of a torpedo, a Pitot said member in non-axial alignment with said tube assembly projecting forwardly from a front 10 .istatic pressure tube and to one side of the first face of said member including a cylindrical velocnamed connection, and a conduit in said member ity pressure tube and a cylindricalfstatic-pressure comrriunicati-ng the last named pipe connection tube surrounding same in` concentric spaced rrewith said annulalpace.

lationship, the rear end oithastaticpressure tube v having a .portion of reduced diameter ,sanda :15 AReferencesited in the file of this patent threaded portion between said portiere ofzrechiced :fe-FOREIGN PATENTS diameter and the remainder thereof,.the velocity ,Number Country Date pressure tube having a portion extending rear- 692 496 Germany June 20 1940 wardly beyond the rear end of the static; pressure i83927.29 Germany May 23 1952 tube, said member having a rst threaded bore for 20 fgdetachebiy receiving:saidthreaded.portonand a OTHER REFERENCES secondiinthreadedbore forreceivingsaidfporton N A, C. A. Report No.` 199, pg. 323, 1924. `ofi reduced. diametenisad SSCOnd- 00m svrprovid- ,-N. A. C.- A i'IeechniealMemo :303;.Ffig- 49, Feb .1:1925.

:faingiairannular space adjacentthe.reanendbfethe 

